Abstract
Structure and magnetic properties of nanocrystalline P6/mmm out-of-equilibrium precursors of hard magnetic R-3m Sm2(Fe,M)17C (M=Ga,Si,) and I4/mmm Sm(Fe,Co,Ti)11 equilibrium phases, are presented. Their structure is explained with a model ground on the R1 − s T5 + 2s formula (R=rare-earth, s=vacancy rate, T=transition metal) where s Sm atoms are statistically substituted by s transition metal pairs. The Rietveld analysis (RA) provides the stoichiometry of the precursors, 1:9 and 1:10, respectively precursor of 2:17 and 1:12 phases. The interpretation of the Mössbauer spectra of the 1:9 and 1:10 phases, is based on the correlation between δ and the Wigner–Seitz Cell volumes, calculated from the structural parameters. The δ behaviour of each crystallographic site versus Co content, defines the Co location while it confirms that of Si and Ga obtained by RA. Substitution occurs in 3 g site, whatever Co or M. The Sm(Fe,Co,Ti)10 and Sm(Fe,M)9C Curie temperature (Tc) are compared to those of the equilibrium phases, the effects of Fe substitution and C addition are discussed. The maximum μ 0Hc is obtained for low M or Co content, for auto-coherent diffraction domain size ∼30 nm. SmFe8.75Ga0.25C and SmFe8.75Si0.25C with Tc of 680 and 690 K, show respectively Mr and μ 0Hc of 58 emu/g, 27 kOe and 95 emu/g, 15 kOe, values higher than those obtained for Sm2(Fe,M)17 carbides.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Kirchmayr, H.R., Burzo, E.: Magnetic properties of rare-earth elements, alloys and compounds. In: Wijn, H.P.J. (ed.) Landolt–Bornstein Handbook Numerical Data and Functional Relationships in Science and Technology, vol. III/19d2, pp. 405–467. Springer, Berlin (1990)
Li, S.H., Coey, J.M.D.: Magnetic properties of ternary rare-earth transition metal compounds. In: Buschow, K.H.J. (ed.) Handbook of Magnetic Materials, vol. 6, pp. 1–83. Elsevier Science, Amsterdam (1991)
Villars, P., Calvert, L.D. (eds): Pearson’s Handbook of Crystallography data for Intermetallics Phases. ASM International, Metal Park OH (1991)
Li, Z.W., Zhou, X.Z., Morrish, A.H.: Magnetic properties of gas phase- prepared R2Fe15Si2C x . J. Phys., Condens. Matter. 6, L283–L286 (1994)
Kong, L.S., Shen, B.G., Wang, F.W., Cao, L., Guo, H.Q., Ning, T.S.: High coercivity in Sm-Fe-Ga-C compounds with the Th2Zn17 structure by melt-spinning. J. Appl. Phys. 75, 6250–6252 (1994)
Shield, J., Meacham, B.E.: Phase formation in hypostoichiometric Sm2Fe17 alloys modified with Ti and C. J. Appl. Phys. 87, 2055–2057 (2000)
Xiao, Q.F., Jhang, Z.D., Zhao, T., Liu, W., Sui, C., Zhao, G.X., Geng, D.Y.: Crystallographic transformations of rapidly quenched Sm10Fe90 − x Ti x and magnetic properties of their nitrides. J. Appl. Phys. 82, 6170–6176 (1997)
Djéga-Mariadassou, C., Bessais, L.: Emergence of order in nanocrystalline SmFe9. J. Magn. Magn. Mater. 210, 81–87 (1999)
Bessais, L., Djéga-Mariadassou, C.: Structure and magnetic properties of nanocrystalline Sm(Fe1-x Co x )11Ti (x ≤ 2). Phys. Rev. B 63(054412), 1–13 (2001)
Djéga-Mariadassou, C., Sab, S., Bessais, L.: Structure and hyperfine parameter correlation in out-of-equilibrium Pr(Fe,Co,Ti)10. Phys. Rev. B 69(064403), 1–7 (2004)
Rodriguez-Carvajal, J.: Recent advances in magnetic structure determination by neutron powder diffraction. Physica. B 192, 55–69 (1993)
Bushow, K.H.J., Van der Goot, A.S.: Composition and crystal structure of hexagonal Cu-rich rare earth-copper compounds. Acta Crystallogr. B 27, 1085–1088 (1971)
Givord, D., Laforest, J., Schweizer, J., Tasset, F.: Temperature dependence of the samarium magnetic form factor in SmCo5. J. Appl. Phys. 50, 2008–2010 (1979)
Djéga-Mariadassou, C., Bessais, L., Nandra, A., Burzo, E.: Crystallographic and magnetic study of metastable nanocrystalline Sm(Fe,Si)9. Phys. Rev. B 68(024406), 1–8 (2003)
Bessais, L., Dorolti, E., Djéga-Mariadassou, C.: Correlation between Sm2(Fe,Ga)17 and its precursor Sm(Fe,Ga)9. J. Appl. Phys. 97(013902), 1–8 (2005)
Bessais, L., Djéga-Mariadassou, C., Nandra, A., Appay, M.D.A., Burzo, E.: Hard magnetic Sm(Fe,Si)9 carbides: structure and magnetic properties. Phys. Rev. B 69(064402), 1–8 (2004)
Teatum, E.T., Gschneidner, K.A., Waber, J.T.: Compilation of calculated data useful in predicting metallurgical behaviour of elements in binary alloys systems. Report LA-4003, UC25, Metals, Ceramics and Materials TID-4500, Los Alamos Scientific Laboratory, (1968)
Bessais, L., Djéga-Mariadassou, C., Koch, E.: Structural and Mössbauer spectral study of the metastable phase Sm(Fe,Co,Ti)10. J. Phys., Condens. Matter 14, 8111–8120 (2002)
Burzo, E.: Permanent magnets based on R-Fe-B and R-Fe-C alloys. Rep. Prog. Phys. 61, 1099–1266 (1998)
Forker, M., Julius, A., Schulte, M., Best, D.: Mössbauer study of the hyperfine interaction of 57Fe in Y1 − s Co5 + 2s and related compounds. Phys. Rev. B 57, 11565–11574 (1998)
Bessais, L., Dorolti, E., Djéga-Mariadassou, C.: High coercivity in nanocrystalline carbides Sm(Fe,Ga) g C. Appl. Phys. Lett. 87(192503), 1–3 (2005)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2008 Springer Science + Business Media B.V.
About this paper
Cite this paper
Djéga-Mariadassou, C., Bessais, L. (2008). Out-of-equilibrium Sm–Fe based phases. In: Gajbhiye, N.S., Date, S.K. (eds) ICAME 2007. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-78697-9_12
Download citation
DOI: https://doi.org/10.1007/978-3-540-78697-9_12
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-87122-4
Online ISBN: 978-3-540-78697-9
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)